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排序方式: 共有7353条查询结果,搜索用时 15 毫秒
1.
Dorota Formanowicz Agnieszka Rybarczyk Marcin Radom Krzysztof Tana Piotr Formanowicz 《International journal of molecular sciences》2020,21(22)
Interleukin 18 (IL-18) is a proinflammatory and proatherogenic cytokine with pleiotropic properties, which is involved in T and NK cell maturation and the synthesis of other inflammatory cytokines and cell adhesion molecules. It plays a significant role in orchestrating the cytokine cascade, accelerates atherosclerosis and influences plaque vulnerability. To investigate the influence of IL-18 cytokine on atherosclerosis development, a stochastic Petri net model was built and then analyzed. First, MCT-sets and t-clusters were generated, then knockout and simulation-based analysis was conducted. The application of systems approach that was used in this research enabled an in-depth analysis of the studied phenomenon. Our results gave us better insight into the studied phenomenon and allow revealing that activation of macrophages by the classical pathway and IL-18-MyD88 signaling axis is crucial for the modeled process. 相似文献
2.
《Oil and Energy Trends》2019,44(3):43-47
Values of net oil imports(-)/exports for Austria, Belgium, Denmark, Finland, France, Germany, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom, Japan, Canada, the United States and Australia. Updated on a monthly basis. Number of imports for Belgium, France, Germany, Greece, Republic of Ireland, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, and Other EU-15 (EU-15), Norway, Poland, Switzerland, Turkey, and Other Europe (OECD Europe), Canada, Chile, Mexico, and the United States (OECD Western Hemisphere), and Australia, Japan, Republic of Korea, New Zealand, (OECD Asia-Pacific), and Total OECED. Current data for Austria, Belgium, Finland, France, Germany, Greece, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, Other EU-15 (EU-15), Czech Republic, Hungary, Poland, Slovakia, Turkey, and Other Europe (OECD Europe), Canada, Mexico, and the United States (OECD Western Hemisphere), Australia, Japan, Republic of Korea, and New Zealand (OECD Asia-Pacific). Updated on a monthly basis. Current data for principal importers of natural gas and the amount in which they import from United States, Republic of Korea, United Kingdom, France, Japan, Italy, Germany and Spain (Table 19.1). Current data for principal exporters of natural gas and the amount they export to Canada, Trinidad and Tobago, the United States, Netherlands, Norway, Russia, Turkmenistan, Qatar, Algeria, Nigeria, Indonesia, Malaysia and Australia (Table 19.2). Updated on a monthly basis. 相似文献
3.
《Oil and Energy Trends》2019,44(10):45-49
Values of net oil imports(-)/exports for Austria, Belgium, Denmark, Finland, France, Germany, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom, Japan, Canada, the United States and Australia. Updated on a monthly basis. Number of imports for Belgium, France, Germany, Greece, Republic of Ireland, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, and Other EU-15 (EU-15), Norway, Poland, Switzerland, Turkey, and Other Europe (OECD Europe), Canada, Chile, Mexico, and the United States (OECD Western Hemisphere), and Australia, Japan, Republic of Korea, New Zealand, (OECD Asia-Pacific), and Total OECED. Current data for Austria, Belgium, Finland, France, Germany, Greece, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, Other EU-15 (EU-15), Czech Republic, Hungary, Poland, Slovakia, Turkey, and Other Europe (OECD Europe), Canada, Mexico, and the United States (OECD Western Hemisphere), Australia, Japan, Republic of Korea, and New Zealand (OECD Asia-Pacific). Updated on a monthly basis. Current data for principal importers of natural gas and the amount in which they import from United States, Republic of Korea, United Kingdom, France, Japan, Italy, Germany and Spain (Table 19.1). Current data for principal exporters of natural gas and the amount they export to Canada, Trinidad and Tobago, the United States, Netherlands, Norway, Russia, Turkmenistan, Qatar, Algeria, Nigeria, Indonesia, Malaysia and Australia (Table 19.2). Updated on a monthly basis. 相似文献
4.
针对流程工业生产系统监测点多,各监测点间具有相关性的特点,提出了一种基于去趋势交叉分析-网络结构熵(detrended cross-correlation analysis-net structure entropy,简称DCCA-NSEn)的复杂机电系统多变量耦合网络建模与状态评估的方法。该方法利用DCCA算法计算多变量两两之间的相关性,构建反映多变量耦合关系的加权网络模型,对监测序列进行滑移求解,得到系统耦合关系网络动态演化模型。利用NSEn方法分析耦合关系网络的结构熵,根据熵随时间的变化趋势对复杂机电系统的服役演化状态进行评估。笔者选取某压缩机组的真实生产数据进行DCCA-NSEn方法验证,然后用耦合去趋势波动分析(coupling detrended fluctuation analysis,简称CDFA)方法对同一组生产数据进行多变量分析,对两方法的分析结果进行对比。结果表明:与DCCA方法相比,本方法具有多变量同时监测评估的优势;与同样是多变量分析的CDFA方法相比,本方法具有评估效果稳定,对系统的异常状态检测效果更明显的优势。 相似文献
5.
Casein in fluid milk determines cheese yield and affects cheese quality. Traditional methods of measuring casein in milk involve lengthy sample preparations with labor-intensive nitrogen-based protein quantifications. The objective of this study was to quantify casein in fluid milk with different casein-to-crude-protein ratios using front-face fluorescence spectroscopy (FFFS) and chemometrics. We constructed calibration samples by mixing microfiltration and ultrafiltration retentate and permeate in different ratios to obtain different casein concentrations and casein-to-crude-protein ratios. We developed partial least squares regression and elastic net regression models for casein prediction in fluid milk using FFFS tryptophan emission spectra and reference casein contents. We used a set of 20 validation samples (including raw, skim, and ultrafiltered milk) to optimize and validate model performance. We externally tested another independent set of 20 test samples (including raw, skim, and ultrafiltered milk) by root mean square error of prediction (RMSEP), residual prediction deviation (RPD), and relative prediction error (RPE). The RMSEP for casein content quantification in raw, skim, and ultrafiltered milk ranged from 0.12 to 0.13%, and the RPD ranged from 3.2 to 3.4. The externally validated error of prediction was comparable to the existing rapid method and showed practical model performance for quality-control purposes. This FFFS-based method can be implemented as a routine quality-control tool in the dairy industry, providing rapid quantification of casein content in fluid milk intended for cheese manufacturing. 相似文献
6.
三门峡水库汛期排沙效果研究 总被引:2,自引:2,他引:0
三门峡水库汛期排沙是解决泥沙淤积问题、控制潼关高程的关键途径。"蓄清排浑"运用以来,非汛期蓄水期库区发生淤积、汛期降低水位运用排泄全年泥沙,基本保持了库区动态冲淤平衡。不同控制水位和入库流量过程存在不同的排沙效果,针对三门峡水库汛期排沙过程的差异,对"蓄清排浑"运用以来汛期排沙特征进行统计,分析了水库敞泄和不同控制水位运用对排沙效果的影响。结果表明,在汛期平水305 m、洪水敞泄的运用条件下,水库排沙具有多来多排的特点,汛期排沙总量与入库含沙量和水量密切相关;完全敞泄时库区冲刷取决于流量大小和敞泄时间,净排沙效率随着水量的增加和敞泄时间的延长而减小,冲刷效率降低;汛期控制运用期,当流量在1000 m~3/s以上时、水位在305~311 m也会产生一定的排沙,排沙效果取决于含沙水流在壅水段的滞留时间和出入库流量之比。研究成果可为三门峡水库运用方式的优化提供依据。 相似文献
7.
It is theoretically and practically significant to synthesize a maximally permissive (optimal) controller to prevent deadlocks in an automated manufacturing system (AMS). With an AMS being modeled with Petri nets, by the existing methods, integer linear programming (ILP) problems are usually formulated and solved to obtain optimal policies by forbidding illegal markings at the same time no legal marking is excluded. Without an efficient technique for solving an ILP, such a method is usually computationally prohibitive. A resource-oriented Petri net (ROPN) is employed to model a class of AMS for resolving the deadlock control problem with maximal permissiveness in this paper. Efficient methods are developed to figure out the key structures in an ROPN model for deadlock prevention. Based on the structural properties of ROPN models, this work explores several types of illegal markings that can be prohibited optimally by structural analysis. For these markings, a deadlock prevention policy can be derived in an algebraic way without solving a notorious ILP problem. For the other markings, linear programming (LP), instead of ILP, approaches are developed to forbid them optimally. Thus, a maximally permissive controller can be developed while the computational cost is reduced greatly. The proposed methods are verified by typical examples in the literature. 相似文献
8.
《Oil and Energy Trends》2020,45(2):47-51
Values of net oil imports(-)/exports for Austria, Belgium, Denmark, Finland, France, Germany, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom, Japan, Canada, the United States and Australia. Updated on a monthly basis. Number of imports for Belgium, France, Germany, Greece, Republic of Ireland, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, and Other EU-15 (EU-15), Norway, Poland, Switzerland, Turkey, and Other Europe (OECD Europe), Canada, Chile, Mexico, and the United States (OECD Western Hemisphere), and Australia, Japan, Republic of Korea, New Zealand, (OECD Asia-Pacific), and Total OECED. Current data for Austria, Belgium, Finland, France, Germany, Greece, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, Other EU-15 (EU-15), Czech Republic, Hungary, Poland, Slovakia, Turkey, and Other Europe (OECD Europe), Canada, Mexico, and the United States (OECD Western Hemisphere), Australia, Japan, Republic of Korea, and New Zealand (OECD Asia-Pacific). Updated on a monthly basis. Current data for principal importers of natural gas and the amount in which they import from United States, Republic of Korea, United Kingdom, France, Japan, Italy, Germany and Spain (Table 19.1). Current data for principal exporters of natural gas and the amount they export to Canada, Trinidad and Tobago, the United States, Netherlands, Norway, Russia, Turkmenistan, Qatar, Algeria, Nigeria, Indonesia, Malaysia and Australia (Table 19.2). Updated on a monthly basis. 相似文献
9.
针对目前应用于电力系统无功优化的智能算法所存在的问题,提出将免疫遗传算法应用于电力系统无功优化问题的措施。免疫遗传算法是将免疫理论和基本遗传算法各自的优点相结合,不仅具有遗传算法的搜索特性,还具有免疫算法的多机制求解多目标函数最优解的自适应特性,对“早熟”问题有所改善,收敛于全局最优。最后,以安康市某区域电力系统为例对算法进行了性能测试,提出了合理的调压措施,结果表明将免疫遗传算法应用于电力系统无功优化问题可以显著降低系统网损,改善电压质量。 相似文献
10.